Government-controlled television reported that the first domestically made rod has already been inserted into the core of Tehran’s research nuclear reactor.

It is unclear if the rod contained pellets or was inserted empty, as part of a test.

The announcement marks another step in Iran’s efforts to achieve proficiency in the entire nuclear fuel cycle from exploring uranium ore to producing nuclear fuel.

It comes amid growing tension between Western powers and Iran after the UN nuclear agency reported Tehran appears to have worked on designing a nuclear weapon.

US President Barack Obama signed more sanctions against Iran into law on Saturday, shortly after Iran signalled it was ready for new talks with the West on its nuclear programme and said it had delayed long-range missile tests in the Gulf.